This invention provides a method of treating cardiac arrhythmia. In particular, the invention provides a method of treatment of arrhythmia comprising administering to a subject suffering from an arrhythmia and in need of said treatment an effective amount of a diarylalkylamine or diarylalkenylamine, thereby converting the arrhythmia to a normal sinus rhythm of the heart.
While the direct causes of arrhythmia remain unknown, several treatments are currently available for converting an arrhythmia to a normal rhythm. The treatment of arrhythmia requires restoring the abnormal rhythm of the heart muscle to normal. No drug has yet been found which is totally effective for treating all types of arrhythmias. Several currently available drugs, such as quinidine, lidocaine, procainamide, and the like, are used to combat arrhythmia; however, the various undesirable side effects of these agents often limit their continued use. Several alkylenediamines have recently been prepared and evaluated as antiarrhythmic agents. Of particular importance among these are certain N,N-dialkyl-N.sup.1 -(2-indanyl)-N.sup.1 -aryl-1,3-propanediamines; see for example, Canadian Pat. No. 910,907.
It is an object of this invention to provide a new method for treating arrhythmia, which method comprises administering a compound selected from among a class of diarylalkylamines or diarylalkenylamines. Several such amines are available and have been widely tested pharmacologically and found to possess various activities. For example, numerous 3,3-diphenylpropylamines have been prepared and tested as analgesics. A complete review of this class of compounds has been compiled by Paul A. J. Janssen, Synthetic Analgesics Part 1, Diphenylpropylamines, Pergamon Press, 1960. Several 4,4-diphenylbutylamines and 5.5-diphenylpentylamines have been prepared and tested by Morikawa, Yakngaku Zasshi 80 475-480 (1960); cf Chemical Abstracts, 50, 5656e. Adamson also prepared several diarylpropylamines, diarylbutenylamines, and diarylbutylamines, as described in British Patent No. 624,117. Additionally, diarylalkylamines and diarylalkenylamines have been prepared and studied by Marxer, Helv. Chem. Acta., 24, 209-225D (1941), and by Blank et al., J. Med. Chem., 271-276 (1969). Hodge prepared several halogenated diarylalkylamines and tested them as bactericides, as described in U.S. Pat. No. 2,681,934. Diarylalkylamines and diarylalkenylamines are reported to be generally useful as antihistamines, anticholinergic agents, local anesthetics, antispasmodic agents, and for treating asthma. According to Janssen, N,N-diisopropyl-3,3-diphenylpropylamine hydrochloride is the most active antispasmodic and antinicotinic agent of the diarylpropylamine series. Additionally, Janssen reported that N-(3,3-diphenylpropyl)piperidine hydrochloride displays weak antispasmodic, antihistaminic, parasympatholytic, antinicotinic, and local anaesthetic activities.
Diarylalkylamines and diarylalkenylamines have not heretofore been used as antiarrhythmic agents. The purported activities possessed by these classes of compounds in no way suggest that they would display a beneficial effect upon the cardiac muscle. An object of this invention is to provide a method of treating arrhythmia comprising administering to a subject an effective amount of a diarylalkylamine or diarylalkenylamine.